This invention relates to spacecraft configurations, and more particularly to spacecraft which can be readily configured from a basic design to adapt to different requirements.
Spacecraft have become important in the fields of communications, military surveillance, monitoring for ecologic conditions, global positioning determination and for weather, including advance notification of storms. The various differing payloads, mission durations and the like make it impossible to use a single spacecraft "bus" to carry the various payloads, because a small bus cannot carry sufficient propellant in addition to its payload for an extremely long mission, whereas a very large bus might be too expensive for the case of a small payload for a short-duration mission. Consequently, the satellite fabrication industry engages in extremely expensive crafting and customization, using such bits and pieces of the design of existing structures as may happen to meet the requirements of the job at hand. The resulting spacecraft must be individually space-qualified, because each differs markedly from the previous spacecraft. The individual crafting and space qualification tends to drive up the cost of the spacecraft and to increase procurement time. Lower costs are desired and shorter procurement times are desired.